If Hillary Clinton wins the presidency, she'll take office in 13 weeks. The left wing of the Democratic Party isn't waiting.

Led by Senators Bernie Sanders and Elizabeth Warren, the progressives are pressuring Clinton on policies and personnel. Sanders wants commitments to support planks in the Democratic platform like a national $15-an-hour minimum wage and expanded government subsidies for college tuition. Warren wants to influence personnel decisions to keep Wall Street and big business from dominating key posts.

"Hillary Clinton is sincere in a number of areas," Sanders said in September in an interview that appears in the Oct. 17 issue of the New Republic. "In other areas I think she is gonna have to be pushed, and that's fine. That's called the democratic process."

Both senators are campaigning strongly for Clinton, who wants their help mobilizing young voters and those on the left wing. That's giving them potential clout and giving Clinton a problem: The more they succeed, the more they'll complicate a White House governing agenda that's likely to include gridlock busting through compromise with conservative Republicans.

Clinton has little choice but to try to accommodate the Warren-Sanders wing while the campaign is still in progress, and probably as president too. Warren, in particular, taps into populist sentiments that transcend the ideological left. Her differences with Clinton, who is more liberal on domestic issues than President Bill Clinton was, are more about tactics than principles; Clinton would be more willing to compromise to win Republican votes needed to accomplish anything big. Compromise is a four-letter word for much of the populist left.

It's a squeeze that is both unavoidable and exceedingly difficult to navigate.

A recent flurry of warnings followed the release by WikiLeaks of e-mails stolen from the account of Clinton's campaign chairman, John Podesta. (U.S. officials have blamed Russia for the leak.) Although substantively rather benign, they reveal a Clinton less hostile to banking interests in private speeches and communications than in her public pronouncements.

The Sanders-Warren wing already has affected the Clinton candidacy, pushing her leftward on issues ranging from financial regulation to health insurance to public-college tuition support.

Warren offered her most pointed warning about appointments in a Sept. 21 speech to the Clinton-friendly Center for American Progress:

When we talk about personnel, we don't mean advisers who just pay lip service to Hillary's bold agenda, coupled with a sigh, a knowing glance and a twiddling of thumbs until it's time for the next swing through the revolving door, serving government then going back to the very same industries they regulate. We don't mean Citigroup or Morgan Stanley or BlackRock getting to choose who runs the economy in this country so they can capture our government. No. This is about people who understand the urgency of the need for rebuilding opportunity in America now and will fight for it with everything they've got.

In communication with the Clintonites, the Massachusetts senator reportedly has said she's not opposed in principle to nominees with Wall Street experience. She says nice things about Gary Gensler, a Goldman Sachs alumnus who ran the Commodity Futures Trading Commission during much of President Barack Obama's administration and is chairman of the Clinton campaign's finance committee. And when she was the top adviser to the Consumer Financial Protection Agency, she pushed Raj Date, a former managing director of Deutsche Bank, for a top post. Warren is critical of Mary Jo White, a prosecutor and corporate lawyer before heading the Securities and Exchange Commission, but praises Federal Reserve chair Janet Yellen, an academic and government economist.

If Clinton tried to tap one of her close Wall Street associates to become Treasury secretary or White House chief of staff, Warren would probably raise hell. That could test Clinton's loyalty to associates such as Tom Nides, a top executive at Morgan Stanley who ran the State Department's office of management and resources from 2011-2013, when Clinton was Secretary of State.

It's not just Wall Street that the populists resist. There was criticism from the progressive wing when Sheryl Sandberg, the chief operating officer at Facebook and a former Treasury official, was rumored to be a candidate for the Treasury post. Last week, Ms. Sandberg said she had no interest in coming to Washington.

Sanders focuses more on policy. At campaign appearances the Vermont lawmaker often holds up a copy of the Democratic platform.

It calls for a sharp increase in the minimum wage, more government-managed health insurance and federal subsidies for many students attending public colleges. Sanders also has noted that the platform calls for breaking up the big banks (so does the Republican platform) and "passage of the 21st-century Glass-Steagall Act." That's a reference to the depression-era law that precluded banks from engaging in both regular banking activities and financial trading and deal making. It was largely repealed in 1999 by legislation signed by Clinton's husband.

Much of the left's agenda would be at cross purposes with another Clinton goal: to break the partisan deadlock of the last couple years by forging compromises with House Speaker Paul Ryan on infrastructure, corporate tax reform and maybe even immigration. A deal with Ryan probably wouldn't be acceptable to Warren or Sanders.

The left probably has one scalp already: Clinton's opposition to the Trans Pacific Partnership. She supported the trade pact before Sanders drew blood by opposing it during the Democratic presidential primaries, and a retreat by some previously supportive Democratic senators (including Clinton's running mate, Tim Kaine of Virginia) have damaged its prospects. Obama hoped to secure passage in a lame-duck congressional session after the election with Republican support.

A year from now it may seem that dispatching Donald Trump, for all his demagoguery, was a cakewalk compared to the challenge of navigating between Warren and Sanders on one side, and Ryan and Republicans on the other.

"The day after the election," Sanders said in the New Republic interview, "we begin the effort of making Clinton the most progressive president that she can become."

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.